Super-accelerating bouncing cosmology in asymptotically-free non-local gravity

TL;DR

This paper explores a non-local gravity model inspired by string theory that exhibits a bouncing cosmology with super-acceleration near the bounce, avoiding the big bang singularity without requiring an inflaton.

Contribution

It introduces a novel non-local gravity framework with asymptotic freedom, providing a method to find homogeneous solutions that describe a bounce and super-acceleration.

Findings

The model produces bouncing cosmological solutions avoiding singularities.

Solutions exhibit super-acceleration near the bounce without inflaton fields.

The approach unifies early and late-time cosmological behaviors.

Abstract

Recently, evidence has been collected that a class of gravitational theories with certain non-local operators is renormalizable. We consider one such model which, at the linear perturbative level, reproduces the effective non-local action for the light modes of bosonic closed string-field theory. Using the property of asymptotic freedom in the ultraviolet and fixing the classical behavior of the scale factor at late times, an algorithm is proposed to find general homogeneous cosmological solutions valid both at early and late times. Imposing a power-law classical limit, these solutions (including anisotropic ones) display a bounce, instead of a big-bang singularity, and super-accelerate near the bounce even in the absence of an inflaton or phantom field.